This invention relates to pollution control systems, and more particularly provides an emission control system for an internal combustion engine. While not so limited, the invention is particularly applicable to automotive and other moving vehicle engines, where the low temperatures obtained as an adjunct may be employed to air-condition or refrigerate part of the vehicle.
The intensified search for improved emission control systems for internal combustion engine has spawned a multitude of proposals. At present, three basic systems have emerged: catalytic treatment of the exhaust gases, after-burners to complete the combustion of exhaust gases, and modification of the engine operating parameters to minimize the amount of emission. Catalysts, however, are readily contaminated by lead compounds in the gases; after-burners require additional fuel; and alteration of operating parameters (e.g. compression ratio, spark timing, etc.) has caused deterioration in gas mileage.
Accordingly, an object of the invention is to provide an emission control system for internal combustion engines which system requires no lead-susceptible catalysts, no fuel-consuming after-burning, and no alteration of the engine itself. An additional object is to provide such system in a form which is particularly applicable to moving vehicles, especially passenger cars, which are driven under a variety of traffic and atmospheric conditions.
Further, an important object of the invention is to provide an emission control system for vehicles, which system produces a low-temperature effluent that can be utilized for air-conditioning or for refrigeration purposes. Thus, as a result of this feature, the installation of an emission control system in an automobile or truck, with little further investment or operating cost, provides the vehicle with a self-contained air conditioning system.
Still other and further objects include the provision of a low cost, durable, and essentially trouble-free emission control system; an emission control system which permits ready withdrawal and disposal of concentrated pollutants; a system which requires no periodic replacement of catalyst inventory; a system which actually enhances the combustion efficiency of an internal combustion engine by reducing the exhaust back-pressure; and a system which permits ready manual or automatic adjustment of flows to optimize engine operation, pollution elimination, and/or refrigeration, depending upon the local demands of temperature, traffic, and legal conditions.